Self-sustained instability, transition, and turbulence induced by a long separation bubble in the footprint of an internal solitary wave. I. Flow topology
Self-sustained instability, transition, and turbulence induced by a long separation bubble in the footprint of an internal solitary wave. I. Flow topology
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DOI：
10.1103/physrevfluids.5.103801
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发表时间：
2020-10
期刊：
影响因子：
--
通讯作者：
T. Sakai;P. Diamessis;G. Jacobs
中科院分区：
文献类型：
--
作者：
T. Sakai;P. Diamessis;G. Jacobs
利用高精度、高分辨率的隐式大涡模拟，研究了在高压内孤立波（ISW）作用下形成的长分离泡驱动下的底边界层（BBL）发展。我们以具有明显横向结构的全局模态的形式了解了初始不稳定性的结构，以及自持续过渡和由此产生的沿床充分发展的湍流的结构。比较了类似的流动特征，以前发现在空气动力学应用中典型的短分离气泡。
Using a high-accuracy-and-resolution implicit Large Eddy Simulation we study the development of the bottom boundary layer (BBL) driven by the long separation bubble which forms under an internal solitary wave (ISW) of depression propagating against a barotropic background current. We obtain insights on the structure of the initial instability in the form of a global mode with a distinct transverse structure, and that of the self-sustained transition and resulting fully developed turbulence along the bed. Comparisons are made to similar flow features previously found in shorter separation bubbles typical of applications in aerodynamics.